In an existing power grid system, when power supply of a power grid is at the peak of electricity usage, electricity consumption from external load increases continuously, which affects load of the power grid, and therefore has great impact on operation of the power grid. When power supply of the power grid is at a low level of electricity usage, there is an abundant amount of electric energy in the power grid, and resources of the abundant amount of electric energy are not utilized, resulting in waste.
A solution in the prior art is: configuring a large-scale energy storage apparatus for a power generation system. When the power grid is at the peak of power supply, the energy storage apparatus performs electric energy compensation for a power grid system. When the power grid is at a low level of power supply, the energy storage apparatus transfers and stores remaining electric energy in the power grid system.
However, independently configuring a large-scale energy storage apparatus often needs large investment. Moreover, the energy storage apparatus generally transfers and stores electric energy in the power grid system in a pumped storage manner, a mechanical energy storage manner, or another manner, and conversion efficiency of these electric energy transfer manners is relatively low.